Self-Aligning and Leak Monitoring Stuffing Box

ABSTRACT

Disclosed is an improved stuffing box that is adapted to articulate within a housing body to accommodate a polished rod misalignment, maintain compression of a graphite stuffing material, prevent cross contamination of debris through the stuffing box interior and provide a means to monitor for fluid leaks. The device comprises a housing having an internally supported stuffing box, where the stuffing box is supported along an angular seat within the housing that allows reorientation of the box as the polished rod passes therethrough. A bonnet applies continuous load onto a gland pusher element using spring washers to compress the stuffing material through discontinuous heat cycles, while an upper and lower wiper element clean the polished rod before entering the stuffing box interior. A lantern ring within the stuffing box provides a venting aperture into the interior of the housing, whereby a pressure indicator monitors for fluid leaks during operation.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.61/557,770 filed on Nov. 9, 2011, entitled “Articulating Stuffing Box.”The above identified patent application is herein incorporated byreference in its entirety to provide continuity of disclosure.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to drilling pumpjacks and stuffing boxassemblies. More specifically, the present invention pertains to a newstuffing box that accommodates misalignment of an oil well polished rod,maintains compression of the stuffing box stuffing material, and furtherprovides a means to monitor for leaks during deployment.

Most oil production involves the pumping of crude oil from undergroundreservoirs to the surface using a pumpjack device, which is areciprocating mechanical device that draws oil through a well and to thesurface for storage and further refining. Pumpjacks generally comprise areciprocating horses head driven by a motor and counter weight. The headconnects to a bridle and further connects to a polished rod. Thepolished rod reciprocates in and out of a stuffing box, which is aclose-fit assembly that cleans the polished rod, prevents debris fromentering or exiting the well, and further prevents fluid from leakingfrom the well during operation. Below the stuffing box, the polished rodconnects to a series of sucker rods that travel the length of the welland downward toward the oil reservoir.

During operation, the stuffing box provides a dynamic seal along thelength of the polished rod. Most conventional stuffing boxes include acentral pathway through which the polished rod travels, while stuffingor packing material is compressed against the sidewalls of the polishedrod to create a fluid seal and to prevent contamination from either sideof the stuffing box from passing therethrough. A common problem withmost conventional stuffing boxes is the propensity for the stuffingmaterial to wear away over time. This problem arises generally when thepolished rod and stuffing box to become misaligned over a period of useand as abrasive contaminants enter the stuffing box and wear away thestuffing material. Misalignment occurs when the mechanical assembliesnaturally loosen or shift over time with respect to one another. Thismisalignment creates lateral loads on the packing material within thestuffing box, distorting the material and causing increased wear andheat. The existence of debris and contaminants within the box onlyexecrate this wear. Eventually, the stuffing box may fail to provide anadequate seal around the surface of the polished rod, requiring workersto replace the packing material or the entire stuffing box assembly toprevent leaks.

The present invention provides a new stuffing box assembly that isadapted to address the current misalignment and wear problems in the artof stuffing boxes. The present invention accounts for misalignment of apolished rod in its construction, maintains compression of the packingmaterial during non-uniform heat cycles, prevents contaminates fromentering the box interior, and actively monitors for leaks from thestuffing box such that the operation can be shut down before acatastrophic leak event occurs. The first drawback of common stuffingboxes is the problem of misalignment of the articulating polished rodwithin the interior of the box, for which the present invention providesan articulating and self-orienting box structure that can pivot androtate to account for side loads and non-concentric polished rodmovement. Another drawback of most stuffing boxes is the build-up ofheat through contaminate friction and non-continuous use in the field(heat cycling). The present invention utilizes a graphite packingmaterial to keep the rod sealed and lubricated, while continuouscompression is kept on the packing material using Belleville springwashers and a pusher gland assembly that can account for thermalexpansion and maintain compression.

Further drawbacks of most common stuffing boxes include inadequate leakdetection and insufficient metallurgy to operate long-term in thetypical oil well environment. Leaks occur most commonly through bottomring failure of a stuffing box, which can create shutdowns for repairsand for environmental inspections, which are both costly and timeconsuming. To address these concerns, the present invention utilizes arelief port to monitor within the stuffing box to monitor pressurewithin the device housing, capturing leaks as they occur for furtheraction to be taken. Both ends of the stuffing box include wiper elementsto remove debris, while the components of the assembly utilize nickelplated or stainless material to prevent corrosion from fluids and acidsthat can otherwise damage the stuffing box components. It is hereindesired to disclose a stuffing box assembly that addresses the majordrawbacks of most common stuffing boxes, and one that fulfills a longfelt need for a reliable and robust assembly that can be readilydeployed and implemented without major changes to existing pumpingassemblies.

2. Description of the Prior Art

Devices have been disclosed in the prior art that relate to stuffingboxes and shaft supports. These include devices that have been patentedand published in patent application publications, and generally relateto improved means of applying compression to a stuffing material oraccommodating for shaft lateral movement through a reciprocating cycle.The following is a list of devices deemed most relevant to the presentdisclosure, which are herein described for the purposes of highlightingand differentiating the unique aspects of the present invention, andfurther highlighting the drawbacks existing in the prior art.

Specifically, U.S. Pat. No. 5,711,533 to Angelo discloses an oilfieldstuffing box that permits lateral displacement of the polished rod usinga pair of flange plates that utilize bolt holes appreciably larger indiameter than the bolts employed to hold the plates together. As thepolished rod moves laterally through its motion, the flanges are capableof moving relative to one another to account for the misalignment inlateral direction. A static seal between the two mating flange platesprevents leaks from occurring during the flange shifts. The stuffing boxis supported by a divided first and second flange, the second beingthreadably connected to the wellhead and the first flange connecting tothe stuffing box and further to the second flange to encapsulate thestuffing box within an interior volume defined by the two flanges. Whilethe Angelo device allows for lateral movement of the polished rod, itsconstruction relies on oversized holes that permit displacement of theflanges relative to one another. This arrangement can lead to wearbetween the flanges and is a less robust means of compensating formisalignment. A seal between the flanges prevents leaks duringmisalignment of the flanges; however no backup system is provided forpreventing leaks after they occur.

U.S. Pat. No. 5,865,245 to Trout discloses a stuffing box gland that isadapted to compress the packing material against an internal polishedrod. The housing includes a central passageway and a lower end forexerting compressive force on the packing within the stuffing box.Within the gland housing is a reservoir for storing lubricant material,whereby the exterior surface of the polished rod and the correspondinginterior surfaces of the gland housing can be lubricated duringoperation. A wiper element is disposed along the lower portion of thehousing to remove debris from the polished rod attached to the rodwithin the well, while an upper housing elastomeric wick removes debrisfrom the polished rod when entering from above the housing. The Troutdevice discloses a stuffing box compression housing and polished rodlubrication device, which reduces wear caused by friction and abrasivedebris. The present invention provides an upper and lower mountedpolished rod debris removal means; however the design and structure ofthe Trout device diverges significantly from that of the presentinvention.

U.S. Pat. No. 5,845,909 to Angelo discloses a stuffing box designed toexert radial compression on an internal polished rod using a glandmember and a plurality of stacked packing rings. The gland membersurrounds the polished rod and encapsulates the packing rings, exertingaxial load on the packing rings, where the rings are annular rubbercarriers having a tapering upper and lower surface and an annularplastic dynamic seal. The tapering shape of the packing rings allows theaxial load from the gland member to transform into radial compression onthe polished rod, creating a dynamic seal to remove debris. The designof the packing rings accounts for thermal expansion of the rubbercarriers and therefore flexing of the packing rings. The Angelo deviceprovides a unique means of exerting load on the polished rod and astructure that accounts for thermal loads; however its design does notaccount for lateral misalignment of the polished rod and the stuffingbox or address a need to monitor for leaks during operation.

U.S. Pat. No. 6,585,416 to Rimmer discloses a self-aligning shaftsupport for a pump pull rod that accounts for both rotary and reciprocalmotion. A guide element bears against a bearing element within ahousing, whereby lateral or angular movement of the shaft is accountedfor at the bearing element interface between the housing and guideelement. An angular face upon which the bearing element rests providesfor angular movement of the guide element, whereby the angular faceestablishes a spherical ledge upon which the guide element rotates andbears against, allowing misalignment of the polished rod via relativemotion along this interface. Similar to the Rimmer device is U.S. Pat.No. 2,628,112 to Herbard, which discloses a self-aligning andlubricating stuffing box having a housing that includes a sphericalsurface concave downward with a bottom bearing ring and an upperspherical surface concave upward with an upper bearing ring. The concavesurfaces support a floating gland assembly that includes the stuffingmaterial and a shaft therethrough.

Both the Rimmer and Herbard devices disclose a stuffing box and shaftsupport that accounts for misalignments between the shaft and the stuffbox housing. The misalignment is handled using a curved bearing surface,in a similar fashion as that provided for in the present invention;however, the design of the present housing provides for misalignmentcorrection, lubrication of bearing elements, a means along the upper andlower portion of the housing to remove debris and sediment, as well as ameans to monitor for well leaks and shut down operation as necessary inthe event of a leak.

Finally, devices having been discloses that account for shaftmisalignment through oversized housings with respect to the interiorstuffing boxes. Both U.S. Pat. Nos. 2,235,289 and 2,267,183 to Dunn andWilliams, respectively, offer interior clearance between the interiorpacking unit making contact with the interior reciprocating shaft andthe exterior housing. The clearance allows lateral movement of thepacking unit as the shaft reciprocates through its motion. Wearingbushings or similar mechanical bearing devices are provided to maintaina secure seal on the shaft while the lateral motion occurs. Thesedevices, while offering a means to account for shaft misalignment, failin the same way as the Trout device, where mechanical clearance isutilized as a means to allow motion. The present invention contemplatesa curved bearing surface together with an interior and exterior housingthat allow the polished rod to angularly move within the device withoutbinding or increasing wear on the stuffing material.

The present invention provides a new stuffing box that maintains thecompression of the stuffing material against a polished rod using aself-orienting construction to account for misalignments, a stuffinggland that accounts for heat cycling, a pair of wiper elements thatremove contaminants from the polished rod and components with sufficientmetallurgy to survive highly corrosive environments. Finally, a ventingaperture allows for leaks to be monitored within a housing outside ofthe articulating stuffing box, allowing operational shutdown beforelarge scale leaks occur. It is submitted that the present invention issubstantially divergent in design elements from the prior art, andconsequently it is clear that there is a need in the art for animprovement to existing stuffing box devices. In this regard the instantinvention substantially fulfills these needs.

SUMMARY OF THE INVENTION

In view of the foregoing disadvantages inherent in the known types ofstuffing box devices now present in the prior art, the present inventionprovides a new stuffing box construction that can be utilized forproviding convenience for the user in oil well operations for deployinga robust and reliable stuffing box assembly.

It is therefore an object of the present invention to provide a new andimproved stuffing box device that has all of the advantages of the priorart and none of the disadvantages.

It is another object of the present invention to provide a stuffing boxdevice having a self-orienting structure that aligns itself with apolished rod passing therethrough to prevent the stuffing box fromreceiving increased lateral loads that would otherwise create higherlevels of friction and wear on the stuffing material.

Another object of the present invention is to provide a stuffing boxdevice that includes graphite stuffing material that is compressed usingspring washers to maintain compression on the stuffing during heatcycling, preventing leaks and loosening of components over time and inbetween long periods of non-use.

Another object of the present invention is to provide a stuffing boxdevice that includes a lantern ring within the stuffing box such that arelief port is provided, whereby leaking fluid will exit the port andinto the stuffing box housing. Within the housing a fluid pressureindicator can be positioned to detect the leak and alert workers of theevent.

Yet another object of the present invention is to provide a stuffing boxdevice that includes an upper and lower wiper ring to remove dirt andsediment from the polished rod prior to entry into the stuffing box,whereby abrasive contaminates are prevented from entering the stuffingbox and wearing the stuffing material.

A final object of the present invention is to provide a stuffing boxdevice that includes nickel plated steel or stainless steel componentsto prevent corrosion caused by contact with well fluids.

Other objects, features and advantages of the present invention willbecome apparent from the following detailed description taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTIONS OF THE DRAWINGS

Although the characteristic features of this invention will beparticularly pointed out in the claims, the invention itself and mannerin which it may be made and used may be better understood after a reviewof the following description, taken in connection with the accompanyingdrawings wherein like numeral annotations are provided throughout.

FIG. 1 shows a cross section assembly view of the present invention.

FIG. 2 shows a cross section view of the body housing.

FIG. 3 shows perspective and overhead view of the body housing.

FIG. 4 shows a cross section view of the stuffing box.

FIG. 5 shows a cross section and overhead view of the seat.

FIG. 6 shows a cross section and overhead view of the gland

FIG. 7 shows a perspective view of the polished rod entering the glandabove the housing.

FIG. 8 shows a cross section and overhead view of the gland pusherelement.

FIG. 9 shows a cross section view and overhead view of the devicebonnet.

FIG. 10 shows a cross section, overhead and perspective view of theported lantern ring.

FIG. 11 shows a perspective view of the assembly in a working state,accepting a polished rod therethrough and connecting to a wellhead.

FIG. 12 shows another external perspective view of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

Reference is made herein to the attached drawings. Like referencenumerals are used throughout the drawings to depict like or similarelements of the stuffing box. For the purposes of presenting a brief andclear description of the present invention, the preferred embodimentwill be discussed as used for preventing misalignment of a polished rodwith respect to the stuffing box, reducing wear, preventingcontamination, preventing corrosion and detecting leaks as they occurwithin the housing. The figures are intended for representative purposesonly and should not be considered to be limiting in any respect.

Referring now to FIG. 1, there is shown a cross section view of thestuffing box assembly 11 of the present invention. The assemblycomprises a housing body 12 having an open interior volume 13 adapted toaccept a rotating stuffing box device 20 therein. The interior of thehousing body 13 comprises a beveled or contoured surface 14 and acontour seat 30 that comprises low friction interface upon which thebase of the stuffing box device 20 is perched thereagainst. The stuffingbox 20 is an elongated member having a rounded upper 22 and lower 21,whereby the rounded lower surface of the stuffing box 20 interfaces withthe seat 30 and contoured surface 14 of the housing 12 to allow relativesliding. This allows the stuffing box device 20 to rotate relative tothe housing 12. The upper portion 22 of the stuffing box connections toa gland pusher 40, which is sandwiched between an upper gland 50 and theupper portion 22 of the stuffing box. Spring washers or Bellevillespring washers 51 and threaded bolts 52 compress the gland pusher 40against the upper portion 22 of the stuffing box, drawing the gland 50against the gland pusher 40.

The gland pusher 40 includes an outer extended diameter and a lowermostreduced diameter portion, whereby the lower portion of the gland pusher40 compresses a stuffing material 60 within the stuffing box 20. Thestuffing box stuffing material 60 is preferably a Grafoil or graphitepacking material. The gland pusher 40 compresses the packing material 60against the outer surface of the polished rod to maintain a dynamicfluid seal thereagainst, preventing well fluid from bypassing thepacking material. The articulating structure of the stuffing box 20itself within the housing 12 allows for misalignment of the polished rodto be accounted for by slight rotation of the stuffing box, preventingside loads and higher levels of wear.

To close off the open interior 13 of the housing body 12, an upperbonnet covering 70 is secured via a plurality of bolted fasteners 71over the housing 12, whereby the bonnet 70 provides an opening withinits center for clearance of the gland pusher 40 during periods ofmisalignment and lateral movement of the push and polished rod. In thisway, the housing 12 remains stationary and is threadably connected 15 toa wellhead, while the polished rod travels in and out of the stuffingbox 20 through the gland 50, gland pusher 40, housing seat 70, andstuffing box interior. The stuffing box 20, gland 50, and gland pusher40 are capable of lateral movement to accommodate slight misalignmentsof the polished rod as it undergoes its reciprocal movement through theassembly. To prevent contaminates from entering the assembly, a firstand second wiper ring 16 is installed on the top and bottom of theassembly to eliminate any debris from being pulled or pushed through thepacking, which would otherwise be an abrasive that creates increasedwear on the packing 60.

Within the interior 13 of the stuffing box is a lantern ring 80 thatsurrounds the polished rod and packing material. The lantern ring 80comprises an orifice that allows leaking fluid to escape the packingmaterial 60 and flow from the stuffing box into the housing interior 13.In the event of a fluid leak, the fluid will flow through the apertureand accumulate within the housing. A pressure sensor or switch ispositioned within the housing to monitor the build-up of fluid. Thissensor can provide workers with advanced notice of a leak as it occursand before it becomes more wide spread. This allows workers to ceaseoperation for replacement of the packing material 60 or repair of any ofthe elements in the assembly. Traditional stuffing boxes will failwithout warning, creating workplace hazards, work stoppages andenvironmental clean-ups. The pressure switch monitors fluid pressurewithin the housing, whereupon a threshold pressure is indicated, asignal can be transmitted to the workers of the leak event.

Referring now to FIGS. 2 and 3, there are shown cross section andperspective views of the housing body 12 of the present invention. Thehousing body 12 comprises a cylindrical body having upstanding sidewalls10, an open upper 17 having outward flanges 18 and a reduced lower thatforms into a threaded coupling 15 adapted to connect directly to awellhead. The interior 13 of the housing accepts the articulatingstuffing box therein, while the base 14 of the interior comprises adownwardly slopping interface upon which the stuffing box is supported.This lower surface also accepts an angled seat, which extends theupwardly angled base of the housing and also provides securement of acircular seal 90 (FIG. 1) that prevents fluid from entering or exitingthe housing during operation. The seat 30, as shown in FIG. 5, is acircular structure having an open interior 45, sloping inner walls 46 tointerface with the stuffing box and a lower channel 19 for placement ofa seal 90 (FIG. 1) between the seat and the housing interior 13.

Along the sidewall of the housing is a vent hole aperture 25. The venthole 25 allows for placement of a pressure switch to shutdown thepumping operation in the event of a packing or seat leak, thereforestemming the leak from continuing. Along the upper portion of thehousing is an outward flange 18 that comprises a plurality of fastenerlocations 26 through which to secure the bonnet fasteners therethroughand enclosure the upper portion of the housing. Finally, the lowermostportion 15 of the housing incorporates a passageway for the polishedrod, whereby the polished rod enters the wellhead and connects to asucker rod in the well. The passageway 15 is an elongated member havingexternal threads for which to threadably engage a wellhead withoutalteration thereof.

Referring now to FIG. 4, there is shown a cross section view of theself-orienting stuffing box 20 adapted to be placed within the interiorof the housing, support stuffing material against the polished rod, andprovide a dynamic seal against the rod as it passes therethrough. FIG. 4shows the stuffing box in an inverted orientation, where the upperportion of the box includes tapped apertures 23 to accept fasteners fromthe upper gland. The box 20 itself comprises an elongated member havinga central passage way 24 to support packing material and a polished rodtherethrough. A ledge 35 within the interior 24 supports the packingvertically as it is compressed downward using the packing glad and gladbolt fasteners. The compression is further assisted using spring washers51 (FIG. 1) that prevent any reducing in compression due to heat cyclingof the material. The packing is compressed downward, causing a naturalexpansion of its cross section such that the packing bears against thesurface of the polished rod as it passes through 24, establishing adynamic fluid seal that prevents well fluid from exiting the well.Positioned at the base of the stuffing box and below the ledge 35 is awiper element 16 (FIG. 1) support 36, which cleans the surface of thepolished rod as it is drawn into the stuffing box interior 24. Thisprevents sediment, debris and thick fluid from contacting the stuffingwithout a first pass of a wiper element 16 (FIG. 1). A second, upperwiper element 16 (FIG. 1) also provides the same functionality, and ispositioned within the upper gland as shown in the cross section in FIG.6.

The stuffing box comprises a largely cylindrical body structure and afirst and second end. The first 22 and second 21 end are adapted to bearagainst the sloped interior surfaces of the housing as the box orientsitself to account for misalignment of the polished rod passingtherethrough. The first 22 and second 21 end of the box comprises aradius, creating a rounded edge 37 and forming a near sphericalinterface on both ends. The interface slides against the sloped interiorsupports of the housing as the polished rod moves through the box inboth upward and downward directions. The box 20 is therefore floatingwithin the housing and can orient itself as necessary given amisalignment of the polished rod as it moves through its motion. Therange of motion of the polished rod and thus the orientation limits ofthe stuffing box are limited by the opening provided by the bonnet 70(FIG. 1), which provides oversized opening to account for lateraldisplacement of the polished rod entering the assembly.

In the event of packing wear and eventual failure, a first and secondventing port 38 is provided along the sidewalls 39 of the stuffing box20 to allow fluid to escape into the interior of the housing. When thisevent occurs, the accumulation of fluid within the interior of thehousing is monitored, such that operations can be ceased to replace thestuffing material. The stuffing itself is a graphite material that hasinherent lubrication; however the stuffing is a wear item that willalways require replacement over its lifetime. The given lifetime of thepresent stuffing box stuffing material is adapted to far exceed mosttraditional stuffing box stuffing material, where abrasive contaminatesand polished rod wear are significantly reduced in the present assembly.

Referring now to FIG. 6, there is shown a cross section view andoverhead view of the upper gland 50. The gland 50 is a circularcompression element that sandwiches a gland pusher element against thestuffing material within the stuffing box interior. The gland 50comprises an open interior to accept the polished rod therethrough,while its section includes a plurality of fastener holes 56 throughwhich bolts are passed to clamp the gland and stuffing box together.Within the open interior, a notch 57 is provided along the interiorsurface to support the second wiper element, which cleans the polishedrod as it passes through the top of the stuffing box assembly. Thiswiper element 16 (FIG. 1) removes dirt, sand and other debris from theexternal environment around the well, preventing contamination andabrasive wearing of the stuffing material that may otherwise occur atthe interface between the polished rod and the stuffing material.Referring to FIG. 7, there is shown a view of the polished rod 100entering the upper gland 50, passing through the wiper element 16,through the bonnet 70 of the housing 12 and into the stuffing boxinterior.

Referring now to FIG. 8, there is shown a cross section view andoverhead view of the gland pusher element 40. The gland pusher element40 is a hollow member having an open interior 65 to accept the polishedrod therethrough and stepped sidewalls 66. The upper portion 67 of thepusher element has a wider wall thickness to interface with the uppergland between the compression fasteners. The fasteners draw the glandagainst the pusher element 40, whereby the base 68 of the pusher elementfits within the interior passageway of the stuffing box and bearsagainst the stuffing material about the sides of the polished rod. Inthis way, the gland pusher element 40 is used to compress the stuffingmaterial and ensure a close tolerance fit between the polished rod andthe stuffing material during operation. Spring washers 51 (FIG. 1)maintain uniform compression of the fasteners against the gland pusher40 and thus compression of the stuffing material.

Referring now to FIG. 9, there is shown a cross section and overheadview of the bonnet 70. The bonnet 70 secures over the housing via aplurality of fasteners that extend through the bonnet and into thehousing upper flange. The bonnet 70 comprises an open interior 72 toaccept the polished rod and the compression fasteners of the uppergland. The opening 72 in the bonnet 70 is adapted to provide freedom oflateral movement of the polished rod, where the diameter of the opening72 determines the extremes of the misalignment for which the stuffingbox and upper gland may accommodate before the fasteners of the gladbear against the interior walls of the opening. The bonnet undersideincludes notches 19 to accept circular seals 90 (FIG. 1) therein. In analternate embodiment, the bonnet lower surface includes angled interiorprojections that provide a curved means for which the upper portion ofthe stuffing box to bear and slide thereagainst, providing a mirroredinterface with respect to the interior seat.

Referring now to FIG. 10, there is shown a cross section, overhead andperspective view of the lantern ring 80 positioned within the passagewayof the stuffing box. The lantern ring 80 is a close fit assembly thatsurrounds the polished rod and provides a first and second port 81through which leaking fluid may escape into through the apertures of thestuffing box and into the open interior of the housing. The lantern ring80 is an elongated sleeve 82 having an upper and lower portion 82 ofgreater outer diameter than the body portion 83 of the sleeve where theports 81 are located to allow the internal pressure within the stuffingbox passageway to be released into the stuffing box and outer chamber.This allows for detection of a leak that is caused by packing orstuffing box seal failure, which may then signal an alarm or shuts thepump down to prevent further damage.

Referring now to FIGS. 11 and 12, there are shown views of the assemblyof the present invention in a working state and from an externalperspective. The upper portion of the assembly comprises an upper gland50 that includes a wiper element, which function to prevent dust anddirt accumulation at the packing entrance and to support bolts thatcompress the packing gland against the internal stuffing material. Theglands 50 and stuffing box rotate with the polished rod 100, therebyeliminating distortion of the packing, as well as eliminating torque onthe rod. The base of the stuffing box bears against a rounded housingseat within the base of the housing that comprises an RTFE or a similarlow-friction surface and an O-ring seal that prevents blow by on theback of the seat. The articulation capabilities of the unit keep thepump aligned at all times. If the polish rod falls out of alignment, thepacking ball may rotate within the housing to keep the packing in linewith the rod.

The base of the housing 12 comprises a threaded wellhead connection 15,allowing the device to be installed onto a conventional oil wellhead110. This enables the device to be used without requiring modificationof an existing oil well head 110. All wetted components of the assemblyare preferably comprised of a nickel-plated steel, stainless steelmaterial, or similar corrosive resistance material. The fluid andsediment within well contains high levels of H₂S acid and othercorrosive material. The use of material suitable for the intendedenvironment enhances the life of each component and reduces replacementcosts. The stuffing compression is held constant within the stuffing boxvia the use of the upper gland, tensioned bolts and Belleville springwashers 51 that maintain uniform tension on the bolts. The washers 51flex in order to limit the stresses placed on the device that occur dueto packing compression, which is caused by changes in temperature andpressure. Additionally, a wiper ring is installed on both the top andbottom of the packing system to eliminate any debris from being pulledor pushed through the packing. The stuffing material is thereforeprevented from high levels of wear as a result of polished rod sideloads and contaminates within the interior of the stuffing box. Thestuffing material itself is a graphite material, which is a low frictionmaterial that reduces friction such that it does not readily overheatand wear. Grafoil packing is the preferred material, in that it does nothave to be lubricated externally and is heat resistant, therebypreventing the device from heating up during periods of dry pumpingwhich can be caused by failure of the pump, loss of suction that canoccur due to gassing, level issues, or by a blocked discharge. Theability to operate without external lubrication frees workers from thetask of monitoring the stuffing box lubrication levels and eliminatesthe requirement of lubricant material. The material itself is lowfriction and thus is uniformly lubricated, preventing pockets of wearand heat generation seen in traditional lubricated stuffing box stuffingmaterial.

It is therefore submitted that the instant invention has been shown anddescribed in what is considered to be the most practical and preferredembodiments. It is recognized, however, that departures may be madewithin the scope of the invention and that obvious modifications willoccur to a person skilled in the art. With respect to the abovedescription then, it is to be realized that the optimum dimensionalrelationships for the parts of the invention, to include variations insize, materials, shape, form, function and manner of operation, assemblyand use, are deemed readily apparent and obvious to one skilled in theart, and all equivalent relationships to those illustrated in thedrawings and described in the specification are intended to beencompassed by the present invention.

Therefore, the foregoing is considered as illustrative only of theprinciples of the invention. Further, since numerous modifications andchanges will readily occur to those skilled in the art, it is notdesired to limit the invention to the exact construction and operationshown and described, and accordingly, all suitable modifications andequivalents may be resorted to, falling within the scope of theinvention.

I claim:
 1. A stuffing box device, comprising: a housing having aninterior volume, upstanding sidewalls, an open upper, and an open lower;a stuffing box adapted to fit within said housing interior, saidstuffing box having sidewalls, a curved upper and lower surface, and anpassageway therethrough; said housing interior volume having a seatproviding a sloping surface upon which said stuffing box curved lowersurface is slideably supported; an upper gland fastened to said stuffingbox upper portion to compress a pusher gland against a stuffing materialwithin said stuffing box interior; a bonnet enclosing said housing openupper, said bonnet comprising an aperture therethrough; said gland,pusher gland, bonnet, stuffing box and stuffing material having apathway to accept a shaft therethrough.
 2. The device of claim 1,further comprising a lantern ring within said stuffing box, said lanternring comprising a sleeve having at least one venting port through whichfluid and pressure may flow to said stuffing box.
 3. The device of claim1, wherein said stuffing box further comprises at least one ventingaperture through which fluid and pressure may flow to said housinginterior.
 4. The device of claim 1, wherein said housing furthercomprises at least one aperture through which pressure is monitoredwithin said housing interior.
 5. The device of claim 1, wherein saidupper gland fasteners compress said pusher gland against said packingmaterial and spring washers maintain tension in said fasteners.
 6. Thedevice of claim 1, wherein said housing interior seat further comprisesa seal to prevent fluid from entering or existing said housing interiorthrough said housing lower.
 7. The device of claim 1, wherein saidhousing open lower further comprises a threadable interface forconnection to a wellhead.
 8. The device of claim 1, wherein saidstuffing box stuffing material is compressed against an internal ledgeand against a shaft within said passageway to establish a dynamic fluidseal about said shaft.
 9. The device of claim 1, wherein said packing isa graphite material requiring no external lubrication.
 10. The device ofclaim 1, wherein wetted components of said assembly comprise a nickelplated steel.
 11. The device of claim 1, wherein wetted components ofsaid assembly comprise a stainless steel.
 12. The device of claim 1,wherein said bonnet secures to a flange about said housing upper via aplurality of fasteners.
 13. The device of claim 1, wherein said bonnetlower surface within said housing interior further comprises a curvedinterface for contact with said stuffing box curve upper surface. 14.The device of claim 1, wherein said upper gland further comprises anupper wiper element that wipes said shaft surface as it passes thereby.15. The device of claim 1, wherein said housing interior seat a lowerwiper element that wipes said shaft surface as it passes thereby.